1. Field
Embodiments of the present invention relate generally to an organic light emitting diode (OLED) display, and a manufacturing method thereof.
2. Description of Related Art
An organic light emitting diode (OLED) display has a self-emissive characteristic, and thus, unlike a liquid crystal display, does not require a separate light source, such as a backlight. Therefore, the OLED display can be reduced in thickness and weight. In addition, since the OLED display has high quality characteristics such as low power consumption, high luminance, fast reaction time, and the like, the OLED display is drawing attention as a next generation display device for a portable electronic device.
The OLED display includes a plurality of organic light emitting elements (organic light emitting diodes) having a hole injection electrode, an organic emission layer, and an electron injection electrode. Light is emitted due to energy that is generated when excitons, which are generated by coupling electrons and holes within the organic emission layer, drop from an excited state to a ground state, whereby the OLED display displays an image.
However, the organic emission layer sensitively reacts to external factors, such as moisture and oxygen. Accordingly, if the organic emission layer is exposed to moisture or oxygen, the quality of the OLED display is deteriorated. Therefore, to protect the organic light emitting elements and to reduce or prevent the moisture or oxygen from penetrating into the organic emission layer, an encapsulation substrate is sealed and combined with the substrate formed with the organic light emitting element through a sealing process, or a thin film encapsulation layer is formed on the organic light emitting element.
Particularly, if the thin film encapsulation layer is used, the overall thickness of the OLED display may be reduced when compared with an OLED display using the encapsulation substrate. Also, the thin film encapsulation layer may enable a more flexible display.
However, the OLED display using the thin film encapsulation is relatively weak with regard to external impact, and defects due to scratches may be easily generated.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.